Marine propulsion mechanisms



United States Patent O 3,175,529 MARINE PROIULSION MECHANISMS Karl Abdon Bergstedt, Goteborg, Sweden, assigner to AB Penta, Goteborg, Sweden Filed Jan. 23, 1963, Ser. No. 253,377 4 Claims. (Cl. 11S-35) This invention pertains to marine propulsion mechanisms, and particularly to means for steering and tilting outboard drive units for boats.

An object of the invention is to provide improved means for tilting outboard drive units for boats and, particularly, for tilting gimbal mounted drive units of the type shown in United States Letters Patent No. 3,006,311.

The novel features which are believed to be characteristic of this invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organization and method of operation, together with further objects and advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying drawings, in which:

FIG. l is a side elevational view of an outboard drive unit including a steering and tilting system shown installed in a boat, portions being shown in fragment and in section for clarity;

FIG. 2 is a side elevational view partially in section of an electrically operated hydraulic pump, and including power and control means represented schematically, comprising parts of the system of FIG. 1;

FIG. 3 is a sectional View of a portion of the pump taken along line 3 3 of FIG. 2.

FIG. 4 is a sectional view of an element of the system of FIG. l; and

FlG. 5 is a perspective view showing the element of FIG. 4 and associated portions partially in fragment of the system of FIG. l.

to drive propeller 7 through universal joint means (not shown) disposed within flexible boot `8, all as described inthe aforementioned patent.

The unit 3, together with yoke 4, are supported on a horizontal pivot 9 and connected therethrough to ears 10 iixed to the boat, whereby the unit and yoke may tilt on pivot 9 in the direction indicated by arrow 11 to clear obstructions, to raise the propeller out of the water and for other purposes.

A steering rod 12 is connected by a ball and socket universal joint 13 to the upper end portion 14 of the unit 3. When theunit is in straight ahead operating position, the rod 12 extends in a direction in or parallel to a vertical plane through the centerline of the boat, and the unit kis also aligned in or parallel to such plane.

The rod 12 extends from joint 13 forwardly and slightly upwardly to and through the boat transom terminating within a cylinder unit 15. The unit 15 is connected to a liexible hydraulic line 16 through which hydraulic lluid is selectively supplied under pressure into cylinder unit 15 from an electrically operated pump unit 17 to raise or tilt the outboard unit and through which fluid returns to the pump when the outboard unit 3,175,529 Patented Mar. 30, 1965 ICC is returning from tilted position to its normal upright drive position shown in the drawing. The pump unit 17 is located in the boat in a position adjacent to unit 15 and is conveniently attached to the transom as shown. The pump unit 17 comprises a pump and sump body 18 and an electric motor 19, the motor being connected through an electric cable 20 to a control switch 21 through which current is supplied to the motor from a battery represented at 22. Switch 21 is located adjacent the operators seat shown in broken lines at 23 and is a three position switch for connecting the motor 19 for forward and reverse rotation and for disconnecting the motor, respectively.

Also arranged adjacent the operators seat is a steering wheel 24 connected through steering cables 25 and 25 to the unit 1S, the wheel being operable in known manner to reel in cable 25 While paying out cable 25 to steer in one direction and to reel in cable 25 while paying out cable 25 to steer in the opposite direction.

Rod 12 and cylinder unit 15 are telescopically interconnected and therefore remain in coaxial alignment. The cylinder unit is swingably mounted to the transom by means including a ball joint socket member 26 shown in broken lines in FIG. 1 and, upon swinging from side to side, causes rod 12 to swing in directions to swing, in turn, the outboard unit on the generally upright axis of pivot 5.

In accord with the invention, operation of switch 21 into one position causes pump unit 17 to force fluid into cylinder unit 15 and, as later further explained, to move rod 12 in a direction into the cylinder unit. Such retraction or drawing in of rod 12 into the cylinder unit pulls portion 14 of the outboard unit upwardly and forwardly tilting the outboard unit on horizontal pivots 9.

The pump unit 17 will be best understood with reference to FIGS. 2 and 3, wherein it will be seen that shaft 27 of reversible electric motor 19 is connected by a pin and socket connection 23 to drive pump rotor 29 in bearing 30. Rotor 29 is coupled to rotatable piston member 31 by means of a knob 32 aiiixed to and extending laterally from the piston member and engaged 1n a socket 33 offset from the axis of the piston member `and from the axis of the pump rotor. Accordingly, the socket `33 and knob 32, upon rotation of the rotor, revolve in a circular path in a plane normal to the axis of the rotor 29, which, with the pump in the upright position shown in the drawing, would be a horizontal plane. The axis of the piston member 31 preferably intersects the axis of the rotor 29, and the point of mtersection is approximately opposite or on a level with the knob 32 and socket 33 whereby the movement of the ball in the socket during rotation of the rotor is minimized.

The axis of the pump piston 31 is inclined with respect to the rotor axis a few degrees, such as substantially 10 degrees in the practical embodiment illustrated. The angle of inclination of the pump piston axis from the rotor axis may vary, however, from as little as 1 or 2 degrees to as much as 20 or 30 degrees, and the exact angle selected will be dependent upon many factors, including the lateral offset of the ball 32 and socket 33 from the axis of the rotor, the desired length of piston stroke, motor speed, desired pressure and volume of fluid to be pumped, and the permissible geometry of the parts. Geometry imposes practical limits as 45 degrees of inclination is approached, and a small angle as used herein is thus intended to be substantially or appreciably less than 45 degrees.

The body portion 34 of piston 33 is slideably and ro-` .tatably disposed iittingly within cylindrical bore 35 in an enlarged or cylinder block portion 36 of partition 37.

` It will'. be een that pump 3 betty portion 3S of unit v17iS hollow. Partition 37 separates the hollow lbody portion 38 into a pressure chamber39 and ak storagerchamber or sump 4t). The chambered pump body is closed by a cover 41 held thereon by bolts, such as bolt 42, and on which the motor 19 is carried, the cover with the` motor ab tachedl thereto removableto permit convenient'assembly and disassembly of the pump.

Cylinder-35 has a closed bottom end pressure portion 43 in which the lower end portion 44 of the pistonmov'es up and down to. pump hydraulic fluid between the sump k4110 and pressure chamber k39 through intake port 45 and outlet port 46. The .pump is reversible and operative Vin aforward direction topump i'luid from sump 40 through intake port 45 into portion 43 of the cylinder and thence through outlet port 46 into Ychamber 39 `from which the liquid may flow into outlet conduit 16, or from which it may be" released through'fa' yspring loaded pressure relief valve 47, which isset to relieve pressures above a predetermined maximum pressure, and thence, through Vconduits 4S and 49 back int suinp 40.V When' the pump is reversed, the piston operates to pump iluid from pressure 7 chamber 39 into sump 40 and the intake and outlet` ports serve then as ,outlet and intake ports. A kcapped fill pipe 50 connected to the pump body 17 in communication with the sump 40 to permit addition lof uid. y Y

The lower end portion 44 ofthe piston is seen to be' relieved, and a side chamfer 51 isprovided on the piston V,extending upwardly from the relieved portion of thepis'- ton along that part 52 oftheY piston which lies between A thercylinde'r ports 45 andz46. Thecham'fer terminates upwardly well below the `Ku'p'pertend 53 of the cylinder.

Upon lcimtinu'ed rotation in the same direction, chamfer 51 opens into communication. with intake port 45 and the piston rises, increasing thevolume in portion 43 of the cylinder below piston endrportion 144, whereby ud ows from sump 4t) through portr45 and chamfer 51 intoY the cylinder. The intake stroke" continues vfor almost a full half revolution, until chamfer 51 moves out of communication with intake port 45 and both portsbecome closed by the land portion 520i the piston, this position being illustrated in' FIG. 3; V'Continued rotation in this forward direction, which, as viewed in FIG. 3 corresponds 'to clockwise rotation, providesrsuccessive pumping and intake strokes to pump fluid from'sump 40 into pressure chamber 39. Operation of; the motorin reversek rotation, to rotate piston 31k ina counterclockwise direction as viewed Vin FIG. 3, will cause, on the other hand,.pumping ot fluid from chamber 39 into sump 4t), since, with such reverse rotation, the pistonv will'move downwardly in a direction inwardly of the cylinder while chamfer 51 communicates withport 45 and upwardly while the chamfer communicates with portY 46,. The pump thus operates in response to `forward Vmotor, rotation to pump iluid from sump dtinto chamber '39 and thence into .conduit 47, and, in response to reverse rotatiorn to pump fluid from chamber 39 into V'sump dtiand to draw iluidlfronr conduit 47. v With the'motor at rest, at least one of ports 45 The chamfer 5,1 is at all'times in unrestricted com munication with the interior o f the lower operative end kportion 43 of theV cylinder around the relieved portion44 of the piston wherebythe uid in cylinder portion ',431and in cham-fer 51 constitutesY a continuousvbody of fluid. I

The portion 52 of the piston acts as a valve in coopera-y `tion with the` ports, closing kboth ofthe ports except when the chamfer 51 is in communication with one or the other of the ports., SIt will be clearly seen in FIG. 3 Athat the 'r chamfer 51 extendsinto kthe piston to a'depthsubstantially less than a ,radius of-'the pistonand that, fauzcordingly, atno time Vdoes the chamfer comprise a communication Y Y between the ports.

A suction relieficheck valved, including apassage# way 67 communicating between sump 40 and .pressure ',chamberis arranged Vin partition 37. 'lhe passageway Y 67 is normally closed by springlloaded ball.valvejmember` 68 but when the pressure in sump 140, which istypicallyA atmospheric pressure, exceeds 'the' pressure lin chamber j 39 Ibyfa small predetermined amount, the valve opens to permit' iluid to ilow from the sump into thel pressure chamber.

f Operation ofathe pumpl results from rotation of rotor 29,1which causes dog or knob 32 to revolve vin a circular path in a'plane whichis atzright'angles tothe axis of rotor j j Y29 but which is inclined from a right angle position ywith -respect tothe axisf `the piston 31. Y The knob 327Land socket 33V are seen to be rounded and offspheroidal shapek to permit smooth rocking 'motion of1therotor.- YAsseen in'FIG. 2, iffthe rotorA is turnedin a'direction't cause 'in the event that pressure-in chamber 39 exceeds the pressure to which relief valve 47 responds,"whereupon this valve opens toy bypass Ylluid from. chamber 39 into the sump through passagewaysi Yand, V49. v

The conduit 16 carries Ailuid, which-is preferably an incompressible hydraulic oilfor hydraulic liquid, to and from theV pump and cylinder unit V15 to control the tilting of the outboard units', unit 15 acting as an expansible chamberdevice. l Y l l 1 The Ydetail-slof the unit 15QandV its` operation may be understood. with reference to kFlG.-'4.lwherein the rodv 12 is shown in maximum housed or telescopedposition in cylin- .der 54, ,corresporuiingV to maximumti-lted positionv of unit 3. l p Therod 12 ycarriesat its end 5 5frwithin cylinder 54 a seal onp-iston 56 against which hydraulic fluid exerts V`pressure when such fluidispulmped VintoV the cylinder Y Ythrough ports 57, which are in; turnconnected through conduit means-,fof which the'position is representedby by broken line at 58, `to, the hydraulic line 164from .the pump. The conduit means V58 will be understood to be locatedin the Vnear wall jofthe cylinder unit 15, which wall -is :omitted in the sectional view of FIG. 4. n

The outer or rearwardV endjof yrod 1,2 comprises Va lball 59 which nests in socket 'mer'nber 6d, 'andball159and' member 60 together comprisethe major relements .ofk 'the ball andsocket joint seen at 13 infFIG. 1. y'Ithe member 60 issuitably lixed'to the upper'endportion 14 of unit 3. v The socket member 26 seen'in FIG. 4 is'lixedly attached and the transom; VRod 12'pas'sesrslidingly throughY bore yknobSZ toi retreat from the viewer;Y chamfer 51 turns towardoutletport 46 ;and,at the same time, `pistonl moves' downwardly in'` the cylinder vforcingV liquid from theoperative lowerportion'of the cylinder, throughv chamfer 51 and'port v4.6,intofpressure chamber 39. f This action continueswith the rotating ofthe rotor until just-i.vr before, the `chamfer 51. cornes into position kfacing toward Y the'viewen, that is,`just before a full halfrevolutiomwhen the valve portionV fSZIofthe pistonclosesotf port 46. At`V this time, knob '32' will havereacheda'position toward the'right asseen/in FIG. 2 land it will be'apparentithat'j-*zv .this position correspondsto maximum inward and 'downward strokecnf-theV piston in cylinder 35.,Y

connected :to the bal'l`62 -andtovextend `forwardly therefrom'withjthe axes of Vcylinder VS'randY cylindricalbore 63 in align-ment. It will be seen,raccordingly, thatl'cylin- Vder unit 15 may swing up landido'wnfand back and-forth about Ythe geometric centerY off-balli@ -asthe ball rotates in socket 26, thatrodf 12. remains-in coaxial alignment in cylinder 54, and'that the `rod ,12 mayV move longitudinally inwardlyand outwardly of cylinder 54through bore 63.

Thepurnpinlg'of iluidthrough;` line/16' randports 57 into cylinder 54 `forces pistonl56. toward the free end 6.4

of cylinder unit '15 retractingrodi-.1,2 into unit 15 'andr '.fpulling Vlball 59 forwardly toward the boat transom, re-

e sultingiinV the tiltingofunit 3 onpivot 9f`rin the direction of arrow 11. Air vent 65 is provided in end 64 of the cylinder. lf pump 17 is operated in a forward direction after unit 3 is in maximum tilted position, or after rod 12 is fully retracted, excess pressure in by valve 47 of the pump.

During normal operation of the outdrive, the pump 17 is not operating. If the outboard unit 3 meets an obstruction, it will kick up on pivots 9 moving rod 12 inwardly of cylinder unit and lthus reducing the pressure in cylinder 54 and line 16 below atmospheric pressure. Valve 66 now opens permitting :liquid to flow through passageway 67 through the partition 37 from sump 40 into chamber `39, whereby to supply the necessary liquid to maintain Ithe line and cylinder 54 filled with liquid at substantially or very nearly atmospheric pressure.

A-s soon .as the obstruction has been cleared, if the propeller is being driven, the outdrive unit will return t0 normal position, liquid being forced through relief valve 47. The adjustment of valve 47, however, is such that the pressure in chamber 39 and cylinder 54 necessary to upwardly tilt the unit when the propeller is inoperative is not sucient to open the valve 47, but the unit may be forced down by the application of about ten or' iifteen pounds of force to the unit at or adjacent the propeller, which rmight be applied manually or by propeller reaction, in a typical exemplary embodiment. In normal use, the outboard unit 3 will be tilted forward by operation of switch 21, such as when the boat is moved into shallow water or is being beached, when the boat is to remain in the water and idle for a period of time .and it is desired to have the unit out of water, when the boat is being hauled out of the water onto a tilt bed trailer, when the boat is being trailered, or when it is necessary to `inspect or replace the propeller. The unit is normally lowered 4from tilted into operating position by reverse operation of pump 17 as selected and controlled by means of switch 21.

In order to lower outboard unit 3 from tilted position into upright position, pump 17 vis caused to operate in reverse by suitable operation of switch 21, and rod 12 moves in a direct-ion outwardly of cylinder 54 while uid ows out of cylinder 54, through ports 57 and conduit means 58 into line 16 and thence into pump chamber 39, through the pump cylinder `35 and finally into sump 4i).

It will be apparent 'from lFIGS. l, 4 and 5 that, as unit 3 tilts on axis 9, the rod ball 59 moves upwardly and 4forwardly and that, to accommodate such movement, the cylinder unit 1S must swing up and down about the center of ball 62. As heretofore explained, the cylinder unit including the mounting ball 62 are `free to swing about the geometric center of the mounting ball 62 in directions to raise and lower forward end 64 of the cylinder -unit thus to accommodate tilting ofthe outboard unit.

'Ihe cylinder unit 1S and rod 12 lare employed in connection with steering of the outboard unit. For this purpose, as seen in FIGS. l and 5, steering cables and 25' are connected to respective ears, of which only one ear 69 is shown, on respectively opposite sides o-f the cylinder unit disposed forwardly of ball 62. A tension spring 70 is shown interposed in cable 25 to take up any slack and maintain the cables taut. The steering wheel 24 is connected `to the cables operable to pay out one while pulling lthe other :and thus to swing the cylinder unit selectively toward the lsides of the boat, as mentioned above. Tiller rod member 12, in response to movement of .the Steering cables, swings on the center of ball 62 in directions to move the rod ball 59 and the upper end 14 of the outboard unit to port and starboard, swinging the outboard unit on upright pivot 5 to steer the boat. The steering action is substantially independent of the tilting action whereby the outboard unit may tilt regardless of :its steering direction and may be steered vwhen tilted. Since movements of the unit on its steering and tilting axes are produced by forces applied by ball 59 to portion 14 line 16 is relieved' CTI of the unit, it will be apparent that bal159 and portion 14 must be located spacedly from both axes.

While only certain preferred embodiments of this invention have been Ishown and described by way of illustration, many modifications will occur to those skilled in the art and it is, therefore, desired that it be understood that it is intended in the appended claims to cover all such modifications as fall within the true spirit and scope of this invention.

What is claimed as new and =what lit is desired to secure by Letters Patent of the United States is:

1. In a marine propulsion mechanism for a vessel comprising a propulsion unit disposed rearwardly of the transom of the vessel and means mounting said unit on the vessel, said mounting means providing tilting and steering movements of said unit about respective horizontal and upright axes located generally between the unit and the transom, a tiller member, joint means connecting said member to said unit, said joint means being spaced rearwardly of both of said axes, an hydraulic cylinder extending generally longitudinally with respect to the vessel, means pivotal-ly mounting said cylinder to said vessel, said tiller member being telescopically engaged in ysaid cylinder, a piston xed to said tiller member and disposed in said cylinder, steering means connected to a portion of said cylinder spaced therealong from said pivotal mounting mean-s therefor for swinging said cylinder on its said pivotal mounting in directions to swing said tiller member and therethrough to swing said joint means laterally from side to side, a reversible hydraulic pump connected to said cylinder, means for operating said pump in one direction to apply force on said piston in a direction to tilt up said outboard unit on said horizontal axis and selectively in the opposite direction to release such tlting force.

2. In a marine propulsion mechanism for a vessel comprising a propulsion unit disposed rearwardly of the transom of the vessel and means mounting said unit on the vessel, said mounting means providing tilting and steering movements of said unit about respective horizontal and upright axes located generally between the unit and the transom, a tiller member, joint means connecting said member to said unit, said joint means being spaced rearwardly of both of said axes, an hydraulic cylinder extending generally longitudinally with respect to the vessel, means pivotally mounting said cylinder to said vessel, said tiller member being telescopically engaged in said cylinder, a piston xed to said tiller member and disposed in said cylinder, steering means connected to a portion of said cylinder spaced therealong from said lpivotal mounting means therefor for swinging said cylinder on its said pivotal mounting in directions to swing said tiller member and therethrough to swing said joint means laterally from side to side, a reve-rsible hydraulic pump connected to said cylinder, said pump comprising a rotatable and reciprocable pump piston having a lateral chamfered portion, a pump cylinder element having two ports alternately and respectively opened by communication with said chamfer and closed by the body of said pump piston in response to rotation of said pump piston, said pump cylinder including a pressure chamber portion in communication with said chamfer and in which the operative end of said pump piston reciprocates to provide pumping action through said ports, means for simultaneously rota-ting and reciprocating said pump piston, said means being selectively reversible to apply force .to said rst piston in a direction to tilt up said outboard unit on said horizontal axis and selectively to apply force to said unit in a direction to oppose such tilting thereof.

3. In an inboard-outboard drive mechanism for a boat, a drive unit, a mounting gimbal `for mounting said unit on said boat including means establishing an upright steering axis and a horizontal tilt axis for said unit, means for steering and tilting said unit on said axes comprising a v ,i 7 Y, telescoping (cylinder and piston rod, 'a first yuniversal pivot connection between lsaid cylinder and said boat', said iirst pivot VVccnniec'tion beinggrlocated above said horizontal axis, a second universal pivot connection between said rod and saidtlnit disposed spacedly from both said axes,

a reversiblegpump for pumping hydraulic uid'to and from said cylinder thereby to cause said second universal pivot connection to approach and to separate from said iirst pivot connection Ytortilt said drive unit between normal upright drive position and a tilted inoperative position, and steering cable means attached to said cylinder spaced therealong from saidiirstpivot for swinging said ylinderand rod back and `forttton vsaid frst'p'ivot and thereby causingsaid second pivotconnection to swing said Vuniton said steering axis.V

In a marine propulsion mechanism Yfor a vessel comprising `a .propulsion unit disposedgrearwardly of the transom of the VVvessel and means mounting said unit on the vessel, said mounting .means providing tilting and steering movements of said unit kabout respective hori-` Y,ne/cted, tofarportion .of said cylinderspaced therealong from said pivotal mounting frneans' therefor forswing'- ving said cylinder onfits said pivotal mounting in, directions to swing`said tiller member and therethrough to swing 'said joint `means laterally from yside to side, a reversible hydraulic pump connected to said cylinder,

anpelectric power source, :a reversible electric motor connected to said pump forV operating` said pump in one direction to apply force on saidV piston in a direction to tilt up said outboard lunit on saidxhorizontal axis and kselectively in the opposite direction to release such tilting force, anda -manuallsvvitch having forward and reverse `positions'for connecting' said source to'zsfaid motor and controlling the direction of operation ofk said -rn-otor and pump. Y t Y t Y 'References Cited bythe Examiner f UNITED STATES PATENTS` 1,733,731` V10/291 Harrisr `10s-157 2,755,766l 7/56 wanzer. Y

2,927,243 t 3/60 Albright 11s-41 x 3,006,311' 10/61 Hansson etal 103-157 3,083,678` 4/63 Leiperti -2115-41 Y FOREIGN PATENTS 110,457 s/zs Austria.

FERGUS s. Mnjnrnromrimm Eiamifaa-f 

1. IN A MARINE PROPULSION MECHANISM FOR A VESSEL COMPRISING A PROPULSION UNIT DISPOSED REARWARDLY OF THE TRANSOM OF THE VESSEL AND MEANS MOUNTING SAID UNIT ON THE VESSEL, SAID MOUNTING MEANS PROVIDING TILTING AND STEERING MOVEMENT OF SAID UNIT ABOUT RESPECTIVE HORIZONTAL AND UPRIGHT AXES LOCATED GENERALLY BETWEEN THE UNIT AND THE TRANSOM, A TILLER MEMBER, JOINT MEANS CONNECTING SAID MEMBER TO SAID UNIT, SAID JOINT MEANS BEING SPACED REARWARDLY OF BOTH OF SAID AXES, AN HYDRAULIC CYLINDER EXTENDING GENERALLY LONGITUDINALLY WITH RESPECT TO THE VESSEL, MEANS PIVOTALLY MOUNTING SAID CYLINDER TO SAID VESSEL, SAID TILLER MEMBER BEING TELESCOPICALLY ENGAGED IN SAID CYLINDER, A PISTON FIXED TO SAID TILLER MEMBER AND DISPOSED IN SAID CYLINDER, STEERING MEANS CONNECTED TO A PORTION OF SAID CYLINDER SPACED THEREALONG FROM SAID PIVOTAL MOUNTING MEANS THEREFOR FOR SWINGING SAID CYLINDER ON ITS SAID PIVOTAL MOUNTING IN DIRECTIONS TO SWING SAID TILLER MEMBER AND THERETHROUGH TO SWING SAID JOINT MEANS LATERALLY FROM SIDE TO SIDE, A REVERSIBLE HYDRAULIC PUMP CONNECTED TO SAID CYLINDER, MEANS FOR OPERATING SAID PUMP IN ONE DIRECTION TO APPLY FORCE ON SAID PISTON IN A DIRECTION TO TILT UP SAID OUTBOARD UNIT ON SAID HORIZONTAL AXIS AND SELECTIVELY IN THE OPPOSITE DIRECTION TO RELEASE SUCH TILTING FORCE. 